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51.
Two large independent sources of data, NSF's University Science Statistics Program Integrated Data Base and CHI Research's bibliometric data base, are brought together in a comprehensive study of the relationships among research resources, as measured by R&D expenditures, and research output, as measured by the quantity and visibility of scientific journal articles. The study is based on approximately 500 U.S. colleges and universities. For each of 11 fields of science, there is strong indication of a linear relationship between R&D expenditures and number of papers. The evidence also indicates a positive relationship between number of cites received per paper and number of papers published, but only for papers published in the basic research journals of the fields of chemistry, physics, and biology.  相似文献   
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A visitor to a new country is assaulted by many changes, both environmental and cultural. Expecting things to be different the visitor is shocked by what he/she finds, thus the term culture shock. A second shock, possibly more traumatic, awaits the international sojourner upon his or her arrival home. The experiences of the returnee typically do not match his or her expectations. Frequently, the individual returning home is not anticipating adjustment difficulties. Compounding the problem is the fact that re-entry has not been widely recognized or researched and thus, little has been done to help individuals to prepare for it.Focusing on international students, who by definition return home, this paper refers to a wide range of social, cultural, political, educational and professional difficulties. The many variables which determine the extent of re-entry shock are identified and discussed. A group program is suggested as one strategy for assisting those about to return home. The results of a pilot study of such a program illustrate how it can be a powerful force to minimize the disorientation and shock of re-entry.This paper serves as a challenge to all those who are responsible or work with international students. Re-entry preparation is also a prerequisite if individuals, institutions, corporations, home countries and host countries are to maximize the benefits and minimize the problems of studying or working abroad.  相似文献   
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This paper reports research on the effects of variations in injection velocity and permeability on the heat transfer and flow through a highly porous medium between two horizontal parallel plates situated at constant distance with constant suction by the upper plate. Due to this type of variation in injection velocity and in permeability the flow becomes three dimensional. The governing equations are solved by adopting complex variable notations to obtain the expressions for the velocity and temperature field. The skin-friction along the main flow direction and rate of heat transfer are discussed with the help of graphs.  相似文献   
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This meta-analysis integrates 296 effect sizes reported in eye-tracking research on expertise differences in the comprehension of visualizations. Three theories were evaluated: Ericsson and Kintsch’s (Psychol Rev 102:211–245, 1995) theory of long-term working memory, Haider and Frensch’s (J Exp Psychol Learn Mem Cognit 25:172–190, 1999) information-reduction hypothesis, and the holistic model of image perception of Kundel et al. (Radiology 242:396–402, 2007). Eye movement and performance data were cumulated from 819 experts, 187 intermediates, and 893 novices. In support of the evaluated theories, experts, when compared with non-experts, had shorter fixation durations, more fixations on task-relevant areas, and fewer fixations on task-redundant areas; experts also had longer saccades and shorter times to first fixate relevant information, owing to superiority in parafoveal processing and selective attention allocation. Eye movements, reaction time, and performance accuracy were moderated by characteristics of visualization (dynamics, realism, dimensionality, modality, and text annotation), task (complexity, time-on-task, and task control), and domain (sports, medicine, transportation, other). These findings are discussed in terms of their implications for theories of visual expertise in professional domains and their significance for the design of learning environments.  相似文献   
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Learners studying mechanical or technical processes via dynamic visualizations often fail to build an accurate mental representation of the system’s movements. Based on embodied theories of cognition assuming that action, perception, and cognition are closely intertwined, this paper proposes that the learning effectiveness of dynamic visualizations could be enhanced by grounding the movements of the presentation in people’s own bodily experiences during learning. We discuss recent research on embodied cognition and provide specific strategies for how the body can be used to ground movements during the learning process: (1) making or observing gestures, (2) manipulating and interacting with objects, (3) using body metaphors, and (4) using eye movements as retrieval cues. Implications for the design of dynamic visualizations as well as directions for future research are presented.  相似文献   
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Measuring perceived social presence in distributed learning groups   总被引:1,自引:0,他引:1  
Social presence—the degree to which ‘the other’ in a communication appears to be a ‘real’ person—has captured the attention of those dealing with learning in groups through computer-supported collaborative learning environments. The concept is important because it affects participation and social interaction, both necessary for effective collaboration and knowledge construction. This article reports on the construction and validation of a self-reporting (Dutch-language) Social Presence Scale to determine perceived social presence in distributed learning groups using computer-supported collaborative learning environments. The result is a one-dimensional scale consisting of five items with an internal consistency of .81. We used a nomological network of similar constructs for further validation. The findings suggest that the Social Presence Scale has potential to be useful as a measure for social presence.  相似文献   
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